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81.
介绍了AutocAD内嵌的VBA语言开发工具和ActiveX技术,分析了它的对象模型以及在VBA环境下编写AcitveX自动化程序的可行性。以母线槽CAD软件系统的开发设计为例,阐明了AutoCAD二次开发的基本理论和方法。 相似文献
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Miles D Jansson E Mai MC Azer M Day P Shadbolt C Stitt V Kiermeier A Szabo E 《Journal of food protection》2011,74(6):980-985
Cassava (Manihot esculenta Crantz) is a widely consumed food in the tropics that naturally contains cyanogenic glycosides (cyanogens, mainly composed of linamarin, acetone cyanohydrin, and hydrocyanic acid). If cassava is not adequately processed to reduce the level of cyanogens prior to consumption, these compounds can lead to the formation of hydrocyanic acid in the gut. Exposure to hydrocyanic acid can cause symptoms ranging from vomiting and abdominal pain to coma and death. In 2008, a survey of ready-to-eat (RTE) cassava-based snack foods was undertaken to determine levels of cyanogens measured as total hydrocyanic acid. This survey was undertaken in response to the New South Wales Food Authority being alerted to the detection of elevated levels of cyanogens in an RTE cassava-based snack food. This survey took 374 samples of RTE cassava chips available in the Australian marketplace. Significant variation in the levels of total hydrocyanic acid were observed in the 317 samples testing positive for cyanogens, with levels ranging from 13 to 165 mg of HCN equivalents per kg (mean value, 64.2 mg of HCN eq/kg for positive samples). The results from this survey serve as a timely warning for manufacturers of RTE cassava chips and other cassava-based snack foods to ensure there is tight control over the levels of cyanogens in the cassava ingredient. Evidence from this survey contributed to an amendment to the Australia New Zealand Food Standards Code, which now prescribes a maximum level for hydrocyanic acid in RTE cassava chips of 10 mg of HCN eq/kg, which aligns with the Codex Alimentarius Commission international standard for edible cassava flour. 相似文献
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BACKGROUND: Sirolimus, a novel immunosuppressant that inhibits cytokine-driven cell proliferation and maturation, prolongs allograft survival in animal models. After a phase I trial in stable renal transplant recipients documented that cyclosporine and sirolimus have few overlapping toxicities, we conducted an open-label, single-center, phase I/II dose-escalation trial to examine the safety and efficacy of this drug combination. METHODS: Forty mismatched living-donor renal transplant recipients were sequentially assigned to receive escalating initial doses of sirolimus (0.5-7.0 mg/m2/day), in addition to courses of prednisone and a concentration-controlled regimen of cyclosporine. We conducted surveillance for drug-induced side effects among sirolimus-treated patients and compared their incidence of acute rejection episodes as well as mean laboratory values with those of a historical cohort of 65 consecutive, immediately precedent, demographically similar recipients treated with the same concentration-controlled regimen of cyclosporine and tapering doses of prednisone. RESULTS: The addition of sirolimus reduced the overall incidence of acute allograft rejection episodes to 7.5% from 32% in the immediately precedent cyclosporine/prednisone-treated patients. At 18- to 47-month follow-up periods, both treatment groups displayed similar rates of patient and graft survival, as well as morbid complications. Although sirolimus-treated patients displayed comparatively lower platelet and white blood cell counts and higher levels of serum cholesterol and triglycerides, sirolimus did not augment the nephrotoxic or hypertensive proclivities of cyclosporine. The degree of change in the laboratory values was more directly associated with whole blood trough drug concentrations than with doses of sirolimus. CONCLUSIONS: Sirolimus potentiates the immunosuppressive effects of a cyclosporine-based regimen by reducing the rate of acute rejection episodes. 相似文献
86.
The case of a patient with an extensive pelvic girdle chondrosarcoma treated with internal hemipelvectomy and intraoperative radiotherapy, followed by adjuvant high-dose external beam radiotherapy, with a successful attempt in achieving long-term local tumor control and limb-sparing treatment is described. 相似文献
87.
S Knapp PT Mattson P Christova KD Berndt A Karshikoff M Vihinen CI Smith R Ladenstein 《Canadian Metallurgical Quarterly》1998,31(3):309-319
We have generated two conditionally immortalized neuronal cell lines from primary cultures of embryonic day 13 (E13) and postmitotic (postnatal day 0; P0) cortical neurons transformed with the temperature-sensitive SV-40 large-T antigen. Two clonal cell lines (CN1.4 from E13 cultures and SJ3.6 from P0 cultures) were isolated and stable maintained in vitro. Both cell lines expressed a number of neuronal markers such as the neurofilaments, glutamic acid decarboxylase 67, neuron-specific enolase, and the BG21 isoform of the myelin basic protein gene. At 34 degrees C, the CN1.4 cell line had elaborated short processes, whereas the SJ3.6 cell line produced long processes that formed a delicate network. When these cell lines were cultured at 39 degrees C, some of the cellular processes grew longer, adopting a more mature neuronal morphology. Interestingly, at 39 degrees C, the in vitro survival of these cell lines differed significantly. Whereas the survival of CN1.4 cell line was greatly unaffected, SJ3.6 cells died soon after they were cultured at 39 degrees C. The cell death of SJ3.6 cells was accompanied by fragmentation and condensation of DNA in their nuclei, indicative of an apoptotic event. Under these conditions, SJ3.6 showed an upregulation of the p75 receptor. When this cell line was cocultured with oligodendrocytes, astrocytes, or glial conditioned media (GCM), there was a marked increase in survival. In contrast, little effect of glial cells or GCM was observed on the CN1.4 cell line. These lines appear to be useful models to study neuronal-glial interactions in addition to neuronal cell death and the effects of glial factors that promote the survival of neurons. 相似文献
88.
MR Kreutz TM B?ckers J Bockmann CI Seidenbecher B Kracht CK Vorwerk J Weise BA Sabel 《Canadian Metallurgical Quarterly》1998,18(20):8278-8291
Cellular-specific splicing of the retinal NMDAR1 receptor (NR1) and expression of NMDAR2 receptor (NR2) subunits in response to optic nerve injury was investigated by in situ hybridization in adult rats. A controlled optic nerve crush led to a clear alteration in the expression of alternatively spliced NR1 variants in the retinal ganglion cell layer (GCL). The NR1-2b and NR1-4b isoforms were preferentially expressed between 2 d and 1 week after injury, whereas expression for all other isoforms remained either unchanged or decreased to barely detectable levels within 4 weeks. Cellular silver grain density for NR2 subunits also declined in the GCL after trauma. To directly test the hypothesis that NR1b expression is crucial for cell survival after axonal trauma, we administered intraocularly an antisense oligonucleotide against the NR1b isoform 2 and 3 d after injury. This led to a drastic loss of retrogradely labeled retinal ganglion cells (RGCs). Antisense targeting clearly reduced retinal NR1 protein levels, as judged by Western blot analysis, but had no effect on the cell number in control retinas. These findings point toward injury-specific changes in alternative splicing of the NR1 receptor, which are crucial for the survival of RGCs after partial axonal trauma. We therefore propose that this reflects an adaptive, rather than a pathogenic, cellular response to neurotrauma. 相似文献
89.
CI Brookes PA White M Staples PJ Oldershaw AN Redington PD Collins MI Noble 《Canadian Metallurgical Quarterly》1998,98(17):1762-1768
BACKGROUND: The variation in stroke volume and pulse pressure characteristic of atrial fibrillation is usually ascribed to time-dependent ventricular filling, implying a single positive relationship between end-systolic pressure and volume, which defines a single state of myocardial contractility. We tested the hypothesis that contractility also varies. METHODS AND RESULTS: We measured the left ventricular pressure and volume continuously with a conductance catheter with catheter-tip micromanometer introduced retrogradely into the left ventricle. The end-systolic pressure-volume relationship was determined in 6 patients in atrial fibrillation undergoing cardiac catheterization for diagnostic purposes and 4 control patients in sinus rhythm undergoing coronary artery bypass graft surgery. The normal positive relationship between end-systolic pressure and volume was found in the control patients, but no such positive relationship was found in any patient in atrial fibrillation. In the latter, the slopes of the linear regressions were either not significantly different from zero or significantly negative (r values <0.08), both results indicating a change in contractility from beat to beat. Significantly negative relationships were found between end-systolic volume and preceding R-R interval (-0.82相似文献
90.